1. Field of the Invention
The present invention relates generally to a device for cleaning a bore or pipe, and specifically to an adjustable device for cleaning casings and liners in oil, gas, and water wells, as well as slots or perforations in the casings or liners.
2. Background
Wells for oil and gas production typically include a central bore drilled from the surface to the reservoir of oil or gas beneath the surface. The bore is often lined with a steel pipe known as a “casing,” which is typically cemented in place. At various times over the life of a well, performance of the well may be improved by cleaning the casing. Cleaning can improve the flow efficiency of the well and also insure that in-line inspection tools can be used to adequately visualize the casing to inspect for damage. Likewise, cleaning can remove unwanted debris, such as scale or paraffins, from slots or perforations in the casing or liner of a well. These and other reasons for properly cleaning an oil, gas, or water well are known and understood in the art.
A brush used to clean a pipeline must have dimensions that allow the bristles of the brush to contact the walls of the casing or liner with enough force to remove the debris therefrom. The casing may, however, have different levels of clearance at different points along its length. Thus, a brush sized to clean one portion of the casing may be too large to penetrate another area of the casing, particularly if significant accumulations of debris are present, or when a liner is encountered, and so on. Likewise, a brush that is small enough to penetrate the heavily obstructed areas may be too small to adequately clean the less obstructed areas.